package com.mengxuegu.gateway.config;

import com.mengxuegu.gateway.enums.ApplicationEnum;
import lombok.AllArgsConstructor;
import org.springframework.cloud.gateway.config.GatewayProperties;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.support.NameUtils;
import org.springframework.context.annotation.Primary;
import org.springframework.stereotype.Component;
import springfox.documentation.swagger.web.SwaggerResource;
import springfox.documentation.swagger.web.SwaggerResourcesProvider;

import java.util.ArrayList;
import java.util.List;

@Component
@Primary
@AllArgsConstructor
public class SwaggerProvider implements SwaggerResourcesProvider {
    public static final String API_URI = "/v2/api-docs";
    private final RouteLocator routeLocator;
    private final GatewayProperties gatewayProperties;
    public static final String discoveryClientRoute = "ReactiveCompositeDiscoveryClient_";

    @Override
    public List<SwaggerResource> get() {
        List<SwaggerResource> resources = new ArrayList<>();
        List<String> routes = new ArrayList<>();
        //存放已经启动的服务路由
        List<String> activeRoutes = new ArrayList<>();
        //取出gateway的route
        routeLocator.getRoutes().subscribe(route -> routes.add(route.getId()));
        //这个是读取配置文件的所有定义过的路由
        List<RouteDefinition> definitionList = gatewayProperties.getRoutes();
        for (String route : routes) {
            if (route.contains(discoveryClientRoute)) {
                String tempRoute = route.substring(discoveryClientRoute.length(), route.length());
                activeRoutes.add(tempRoute);
            }
        }
        //结合配置的route-路径(Path)，和route过滤，只获取有效的route节点
        definitionList.stream().filter(routeDefinition -> activeRoutes.contains(routeDefinition.getId()))
                .forEach(routeDefinition -> routeDefinition.getPredicates().stream()
                        .filter(predicateDefinition -> ("Path").equalsIgnoreCase(predicateDefinition.getName()))
                        .forEach(predicateDefinition -> {
                            String location = predicateDefinition.getArgs().get(NameUtils.GENERATED_NAME_PREFIX + "0").replace("/**", API_URI);
                            String name = routeDefinition.getId();
                            SwaggerResource resource = swaggerResource(name, location);
                            resources.add(resource);
                        }));
        return resources;
    }

    private SwaggerResource swaggerResource(String name, String location) {
        SwaggerResource swaggerResource = new SwaggerResource();
        swaggerResource.setName(ApplicationEnum.getNameByKey(name));
        swaggerResource.setLocation(location);
        swaggerResource.setSwaggerVersion("2.0");
        return swaggerResource;
    }
}
